ABC
The actor, who is currently promoting "The Huntsman: Winter's War," stopped by "Jimmy Kimmel Live!" and told the host about his bout of altitude sickness.
When climbing at such high altitudes, standard procedure dictates taking a break at certain heights to help bodies adjust to the low oxygen levels, but Hemsworth's body wasn't adjusting.
"We went to 2,000 meters, then 3,000, and I honestly started to kind of lose my mind," Hemsworth said. "Just completely irrational, overly sensitive to the most trivial sort of silly things."
Hemsworth's wife, Elsa Pataky, began to notice that something was off, but Hemsworth said he kept denying it.
After getting to 4,000 meters, Hemsworth was struggling.
"My breathing is getting worse, like Darth Vader meets Daffy Duck," Hemsworth said. "She eventually ignores me, runs and tells the guides. They come in, take one look at me and say 'get him off the mountain.'"
He was given an oxygen mask and was flown down the mountain via helicopter. While he's okay now, it was nearly a deadly experience for the actor.
"Apparently the oxygen in my lungs, the next day would've been oxygen in my brain, and then goodnight," Hemsworth said. "We wouldn't be sitting here."
"Maybe it's because you're so handsome," Kimmel joked. "You're not meant to be up in the mountains away from others, you're meant to be down amongst the people, bringing joy to their eyes."
Watch the interview below: